In general, exhaust heat of exhaust gas emitted from an engine of a vehicle is regarded as unnecessary heat, that is, waste heat, having a lower utility value and is abandoned into the air. The exhaust heat of the exhaust gas is a substantial amount of energy that occupies about 30% of the total calorific value of fuel and is gradually increased in terms of a utility value. Accordingly, recently, various types of exhaust heat recovery devices have been used, such as, a heater which is able to heat the interior of a vehicle using the exhaust heat of the exhaust gas, a warmer, which is able to warm up coolant or oil using the exhaust heat of the exhaust gas, and a thermoelectric module which is able to perform thermoelectric power generation using the exhaust heat of the exhaust gas.
In general, exhaust heat recovery devices have mutually different temperature characteristics in a driving temperature or an endurance temperature. Accordingly, to efficiently recover exhaust heat of exhaust gas, various types of exhaust heat recovery devices have been installed within a vehicle. However, conventionally, since an exhaust heat recovery system has not been developed in which the various types of exhaust heat recovery devices are integrated with each other, the exhaust heat recovery devices are occupied at an excessively large percentage based on the whole volume of the vehicle, and the number of parts (e.g., a valve necessary for the switch of a fluid passage of the exhaust gas) for installing the exhaust heat recovery devices is excessively increased.